Sliding apparatus of a movable bridge

ABSTRACT

There is disclosed a bridge extendable away from, and retractable back towards, a quay, and including winch means, at least one flexible connection for extending the bridge and at least one flexible connection for retracting the bridge, said flexible connections coupling the winch means to the bridge, one of said flexible connections being wound and the other unwound by the winch means upon operation thereof to extend or retract the bridge, and weights suspended from said flexible connections between the winch means and the bridge. When a boat is secured to the outboard end of the extended bridge, movement of the weights allows the bridge to follow movement of the boat.

United States Patent Mori et al.' [451 June '13, 1972 SLIDING APPARATUSOF A MOVABLE 598,012 93 BRIDGE 1,368,841 2/l92l Robb 474,l25 5/ l892Haynes ..l4/54 [72] inventors: Kunlo Mori, Sohka; Yoshlo Shlrage, Fu-

jisawa, both of Japan Primary Examiner-Jacob L. Nackenoff An --S 81B[73] Assignee: Nippon Kokan Kabushiki Kaisha, Tokyo, omey embers lakeJapan [57] ABSTRACT [22] Filed: W" 1970 There is disclosed a bridgeextendable away from, and 76, retractable back towards, a quay, andincluding winch means, [2] 1 App] No 068. at least one flexibleconnection for extending the bridge and at least one flexible connectionfor retracting the bridge, said [30] Foreign Application Priority Dataflexible connections coupling the winch means to the bridge, one of saidflexible connections being wound and the other Dec. 28, 1969 Japan ..44/105076 unwound by the winch means upon operation thereof to tend orretract the bridge, and weights suspended from said "14M3 flexibleconnections between the winch means and the bridge. [51] Int. Cl ..E0ld15/10 When a boat is secured to the outboard end of the extended [58]Field of Search "14/433, 54, 62; 104/124 bridge, movement of the weightsallows the bridge to follow movement of the boat. 56 R t C'ted e erences6 l sure UNITED STATES PATENTS arrangement and the bridge.

1 sunmc APPARATUS or A MOVABLE BRIDGE FIELD OF THE INVENTION The presentinvention relates to movable bridges for loading and unloading boats ata quay; for example ferry boats canying automobiles and passengers, Inparticular, it relates to bridges whichare extendable and retractablerelative to a quay. 1

BACKGROUND OF THE INVENTION Such bridges can suffer from thedisadvantage that movement of a boat secured to the outboard end of theextended bridge can damage the driving means for moving the bridge andcan break the coupling between the bridge and the boat.

. SUMMARY OF THE INVENTION In particular, the present invention relatesto an apparatus which assists in connecting and disconnecting the bridgeeasily from the boat when said boat is alongside the quay.

It is an object of the present invention to provide an extendable andretractable bridge which when it is extended and the outboard endthereof is secured, for example pivotally, to the boat, is still able tomove with the movement of said boat. The present invention also providesapparatus having a simple structure which prevents accidental damage todriving means, for extending and retracting the bridge, resulting frommovement of the boat, and uncoupling of the bridge from the boat.

According'to the invention there is provided a bridgear. ranged so as tobe extendable away from, and retractable back towards, a quay andcomprising a winch arrangement coupled to the bridge by at least oneflexible connection for extending the bridge and at least one flexibleconnection for retracting the bridge, one of said flexible connectionsbeing wound and the other unwound by the winch arrangement uponoperation thereof, whereby to extend or retract the bridge, and a weightsuspended from each flexible connection between-the winch BRIEFDESCRIP'HON or' THE DRAWING An embodiment of the invention will now bedescribed, by way of example, reference being made to the accompanyingdrawing, which shows a side elevation of a bridge according to theinvention. 1

DESCRIPTION OF SPECIFIC EMBODIMENT In the drawing 1 is a bridge which ismovable down an inclined surface at aquayside on rotatable wheels (notshown in the drawing) or the like, so that it can b'e extended away fromand retract back towards the quay. Although not shown in the drawing,the outboard end of said bridge is preferably supported by some form ofelevating apparatus so that that end can be adjusted verticallyaccording to the height of the gangway of a boat when said boat comesalongside the quay.

Guides 2, 3 in the form of pits are arranged in the base over which thebridge 1 moves forward and backward, and stops in the form of shoulders2a, 3a are provided near the upper ends of the guides 2, 3. Above thetops of the guides spaced apart pairs of guides wheels 4a, 4band 5a,.5bare supported on bearings 6 and 7.

Within said guides 2, 3 are pulley blocks 10, 11 from which aresuspended weights 8, 9. Flexible connections consistuted by wire ropes12a, 12 b pass around the pulleys a, 11a of said pulley blocks 10, 11and said guide wheels 40, 4b, 5a, 5b

in a way to be described below. A return guide wheel 13 for supportingthe wire rope 12a is supported on bearing 14. Wire ropes 12a and 12b areattached at one end to wire attachment points 16 and 15 on the lowerside of bridge 1 and at their other ends to a winch l7.

Wire rope 12a is for extending the bridge. From the wire attachementpoint 16 nearer the front or outboard end of the bridge 1 it passes overthe return guide wheel 13 and then fonns a loop between pulleys 4a and4b, the pulley block 10a being at the bottom of the loop. From there therope 12a pases toone of the winding drums for the winch 17. The otherwire rope 12b passes from attachment point 15 at the rear of the bridge1 and forms a loop between pulleys 5a and 5b, the pulley block Ila beingsuspended from the bottom of the loop. It is then wound on to anotherwinding drum of the winch l7.

When the winch 17 is actuated, one of the wire ropes 12a, 12b is woundand the other unwound from winch 17.

Assuming wire rope 12a is being wound, weight 8 becomes lifted until itcomes into contact with stop 20 and thereafter the bridge 1 movesforward to project from the quay. The elevating means is used to placethe outboard end of the bridge 1 on a boat alongside and that end isthen secured to the boat. After the bridge 1 is thus supported by theboat, wire rope 12a is unwound so that both ropes are loosened and theweights 8, 9 are both at least partly lowered, thereby giving thearrangement flexibility and permitting free movement of the bridge 1.

Thus, if the boat pushes the bridge back theweight 9 descends and theweight 8 is elevated. If the boat slightly moves forward, then theweight 9 is lifted and the weight 8 descends. Thus, the bridge movesbackwardly and forwardly following the movement of the boat.

When the bridge 1 is to be retracted, wire rope 12b is wound in by thewinch l7 and the other wire rope 12a is unwound. Thus, the bridge 1 isretracted once weight 9 has contacted its stop.

In summary, in the described embodiment a wire rope for wound andunwound respectively by said winch and are attached to the bridge. Aweight is suspended on both wire ropes via a pulley device placedbetween said winch and bridge, so that the bridge can be drivenoutwardly and inwardly relative to the quay by means of said winch.Also, when the bridge is extended outwardly and the end fixed to a boatalongside the quay, said bridge can move to follow the movement of theferry, so that no accidental damage to the bridge or the driving meansis caused by the ,movementof the boat and also the bridge is notdetached from the .boat. Furthermore, when weights are suspended asaforementioned, the wire ropes are never loose, whether said bridge isin motion or not, which .would otherwise be an undesirable factor.

' forms a retracting flexible connection means for retracting thebridge, both of these flexible connection means being coupled with thewinch means 17. The winch means 17 is operatively connected to both ofthe flexible connection means 12a and 12b to provide therein,respectively, lengths greater than the lengths required to extend fromthe bridge to the winch means, at least when the bridge is in itsextended position, by

an amount suflicient to render the bridge in the latter position freelymovable independently of the winch means. The weights 8 and 9 form ameans operatively connected with both of the flexible connection means12a and 12b to maintain the latter taut while the extended bridge isfreely movable independently of the winch means, so that in this wayundesirable looseness in the wire ropes is eliminated.

We claim:

1. In a bridge extendable into an extended position extending away from,and retractable back towards, a quay, winch means, at least oneextending flexible connection means for extending the bridge into saidextended position thereof and at least one retracting flexibleconnection means for retracting the bridge, said extending andretracting flexible connection means coupling the winch means to thebridge, one of said flexible connection means being wound, and the otherunwound by the winch means upon operation thereof to extend or retractthe bridge, and said winch means being operatively connected to saidextending and retracting flexible connection means for providing thereinlengths, respectively, greater than the lengths required to extend fromthe bridge to said winch means, at least when said bridge is in saidextended position thereof, by an'amount sufiicient to render the bridgein the latter position freely movable independently of said winch means,and means operatively connected to said extending and retractingflexible connection means between the winch means and the bridge formaintaining both of said flexible connection means taut when the bridgeis in its extended position so as to eliminate undesirable looseness insaid extending and retracting flexible connection means while saidbridge remains freely movable in its extended position independently ofsaid winch means.

2. A bridge as claimed in claim 1 in which said means for maintainingsaid extending and retracting flexible connection means taut includesweights suspended from the extending and retracting flexible connectionmeans on pulley blocks.

3. A bridge as claimed in claim 2 in which the bridge has an inboard endportion, said retracting flexible connection means for retracting thebridge extending from said winch means to said inboard end and includinga downwardly extending loop,

spaced apart pulleys supporting said loop, and one of said weights beingsuspended from said loop.

4. A bridge as claimed in claim 3 comprising a return pulley, saidextending flexible connection means for extending the bridge extendingfrom said winch means round said return pulley to the bridge, a seconddownwardly extending loop situated between the winch means and thereturn pulley, and spaced apart pulleys supporting said second loop, andone of said weights being suspended from said second loop.

5. A bridge as claimed in claim 4, comprising stops coacting with saidweights for limiting movement of the weight connected to said extendingflexible connection means during movement of the bridge to its extendedposition and for limiting movement of the weight connected to saidretracting flexible connection means during retraction of the bridge.

6. A bridge as claimed in claim 5 in which the stops coact with saidweights for limiting movement thereof during extension and retraction ofthe bridge.

a a k a:

1. In a bridge extendable into an extended position extending away from,and retractable back towards, a quay, winch means, at least oneextending flexible connection means for extending the bridge into saidextended position thereof and at least one retracting flexibleconnection means for retracting the bridge, said extending andretracting flexible connection means coupling the winch means to thebridge, one of said flexible connection means being wound, and the otherunwound by the winch means upon operation thereof to extend or retractthe bridge, and said winch means being operatively connected to saidextending and retracting flexible connection means for providing thereinlengths, respectively, greater than the lengths required to extend fromthe bridge to said winch means, at least when said bridge is in saidextended position thereof, by an amount sufficient to render the bridgein the latter position freely movable independently of said winch means,and means operatively connected to said extending and retractingflexible connection means between the winch means and the bridge formaintaining both of said flexible connection means taut when the bridgeis in its extended position so as to eliminate undesirable looseness insaid extending and retracting flexible connection means while saidbridge remains freely movable in its extended position independently ofsaid winch means.
 2. A bridge as claimed in claim 1 in which said meansfor maintaining said extending and retracting flexible connection meanstaut includes weights suspended from the extending and retractingflexible connection means on pulley blocks.
 3. A bridge as claimed inclaim 2 in which the bridge has an inboard end portion, said retractingflexible connection means for retracting the bridge extending from saidwinch means to said inboard end and including a downwardly extendingloop, spaced apart pulleys supporting said loop, and one of said weightsbeing suspended from said loop.
 4. A bridge as claimed in claim 3comprising a return pulley, said extending flexible connection means forextending the bridge extending from said winch means round said returnpulley to the bridge, a second downwardly extending loop situatedbetween the winch means and the return pulley, and spaced apart pulleyssupporting said second loop, and one of said weights being suspendedfrom said second loop.
 5. A bridge as claimed in claim 4, comprisingstops coacting with said weights for limiting movement of the weightconnected to said extending flexible connection means during movement ofthe bridge to its extended position and for limiting movement of theweight connected to said retracting flexible connection means duringretraction of the bridge.
 6. A bridge as claimed in claim 5 in which thestops coact with said weights for limiting movement thereof duringextension and retraction of the bridge.